The semiconductor industry has experienced exponential growth, and has progressed in pursuit of higher device density and performance, and lower costs. Since the fabrication of a semiconductor device is complicated and includes numerous steps, accuracy is a very important issue to each step. Hence, it is crucial to monitor the steps and inspect whether the processing conditions of the steps meet the requirements to ensure the property and/or performance of inline production. By doing so, process errors can be decreased, which lowers the possibility of damage or waste and thereby reducing the cost. However, in current technology, complex procedures are required for monitoring the inline production. Accordingly, the method for monitoring the inline production has to be continuously improved.